Open source database provider 10gen is expanding into storage services, offering a hosted backup service for its flagship MongoDB data store.

Using 10gen's backup service would save users from the work of setting up their own backup copies, which can be a challenge to implement, according to a 10gen statement announcing the new service. Administrators would have to set up a backup service that would need to be reliable, and not procure too much, or too little, hardware, for the job.

10gen's backups are initiated by a lightweight agent installed on the primary data store server. The backup service is incremental: every six hours, any changes made in the primary data store are copied to the backup locations. The data is transferred over the Internet and is encrypted through SSL (the Secure Socket Layer).

To restore data, the user must provide two forms of authentication. Data can be restored not only to the last known good version, but any version in point in time. For redundancy, MongoDB stores the backups at multiple locations, in different geographic regions.

The backups can be used to restore the original if it is lost or becomes corrupted, but also can be used for development purposes, or to provide copies of the data without impacting performance of the primary servers.

The initial copying of the data does not cost anything, though subsequent changes cost US$2 per gigabyte to ingest. Users will also pay $0.01 per gigabyte for snapshot creation and $0.08 per gigabyte per month for snapshot storage. Restoring the data store is free. Customers can pay their monthly bills with a credit card.

This is not the first online MongoDB service the company offers. It also provides the free MongoDB Monitoring Service (MMS), which has more than 17,000 users.

The company is now offering a limited release of the service, called MMS - Backup, and will make it available to everyone later this year. The company did not specify if it was running the backup servers itself, or if it had contracted with a commercial cloud provider, such as Amazon Web Services.

Created in 2007, MongoDB is a document store that is particularly well-suited for storing large amounts of material, good for big data-based analysis, content management and for backing up data for mobile and social networking applications. The software has been downloaded over four million times, and has been used by organizations such as Craigslist, Disney, Electronic Arts, eBay, Foursquare, Intuit, LexisNexis, MTV, and Salesforce.com.